Hi Pilates
Sorry you have to go through this. I can give you a general answer of what to expect in the days after the surgery.
Though it varies with each person, hospitalization is usually 4-6 days if your overall health is good. The criteria for discharge include the return of bowel function (meaning passing gas and stool through your stoma), pain controlled on oral medication, no fevers/infection, drinking adequate fluids to remain hydrated, being able to keep food down, walking independently, and resuming some of your personal care.
You should be independent with your ileostomy in terms of emptying your pouch yourself, and understand the basics of changing your pouch. Most times my patients have a home health nurse to continue teaching pouch change as hospitalization is so short. If you accomplish this while hospitalized, that's great!
Return of bowel function can be either immediate (1 day) or delayed a few days; everyone is different. 2-4 days is pretty standard. They will usually start you on liquids when they hear bowel sounds (stomach growling) and see gas in the pouch. Usually, the stool is very liquid initially and can be high volume (1-3 liters or quarts/day). It should slow down before leaving the hospital and even more over the next few weeks, and the stool usually thickens with eating. Feeling gassy and bloated is not unusual for the first 10 days. The important part is to remain hydrated, and it can be difficult to drink if you feel bloated. Drinking liquids in smaller amounts and more frequently often is easier than downing a larger volume at once. Warm or room temperature fluids will also make you less gassy/bloated than ice-cold drinks or carbonated beverages.
Most people can expect to have to empty their pouch 7-9 times per day initially. Empty when 1/2 to 1/3 full. Most of my patients tell me they do need to empty at least once during the night.
Recovery to the point of returning to work or enjoying your normal lifestyle is usually 6-8 weeks if otherwise healthy. It would be helpful to have someone to shop, drive you to appointments, house clean, help with meals. Walking is great exercise to get your energy back, but take it slow. There may be some emotional ups and downs with going through any surgery. Having a new stoma is an adjustment, but the bright side is hopefully no more fistulas and a return to better health.
Given they are resecting your pouch, you should speak with your physician about the need for supplementing B-12 and possibly requiring medication to slow down your stool output (i.e., Imodium or Lomotil) as you will be missing a bit more of your small intestine to absorb fluids and nutrients.
I know this is very general. The folks here could give you a more personal account and tips to get through this more easily.
Best wishes for a speedy recovery!